The incidence of alcohol-related disease is different in different populations. The allelic frequency of the enzymes thought to be primarily responsible for alcohol metabolism is also different in these populations. Alcohol distributes in the total body water, so doses of alcohol should be made on a g/l of total body water basis instead of a g/kg basis. Previous attempts to compare ethanol metabolism in different ethnic groups did not compare individuals of similar genotype or adjust the dose to account for possible differences in total body water.